package collection;

import java.util.ArrayList;
import java.util.Collection;

public class CollectionDemo {
    public static void main(String[] args){
        Collection c=new ArrayList();
        c.add(new Point(1,2));
        c.add(new Point(3,4));
        c.add(new Point(5,6));
        c.add(new Point(7,8));
        c.add(new Point(9,0));
        c.add(new Point(1,2));
        System.out.println(c);

        Point p=new Point(1,2);
        boolean contains=c.contains(p);
        System.out.println("是否包含:"+contains);//true

        //boolean remove(Object o):从当前集合中删除与给定元素o的equals()比较
        //为true的元素，只删除一次
        c.remove(p);
        System.out.println(c);
        c.remove(p);
        System.out.println(c);

        Collection cc=new ArrayList();
        Point pp=new Point(1,2);
        cc.add(pp);//将pp添加到cc中--------将pp的引用装到cc中
        System.out.println("pp:"+pp);//(1,2)
        System.out.println("cc:"+cc);//[(1,2)]

        pp.setX(100);
        System.out.println("pp:"+pp);//(100,2)
        System.out.println("cc:"+cc);//[(100,2)]






        /*
        Collection c=new ArrayList();
        c.add("one");
        c.add("two");
        c.add("three");
        c.add("four");
        c.add("five");
        //集合重写了Object的toString()方法，返回格式如下
        //[元素1.toString(),元素2.toString(),元素3.toString(),....]
        System.out.println(c);
        System.out.println("size:"+c.size());//输出集合的元素个数
        System.out.println("是否为空集"+c.isEmpty());//false

        c.clear();//清空集合
        System.out.println("集合已清空");
        System.out.println(c);//[]
        System.out.println("size:"+c.size());//0
        System.out.println("是否为空集:"+c.isEmpty());//true

         */
    }
}
